Figure I should make a post to my very early basic fishing game that I used for my May One Game A Month and using it for this. It is still in the works, right now you are a rectangle as a fish and swimming around to collect food (spheres) and thats about it.

Will be adding the growth aspect of the fishFish food adds to your energy which you use energy to swimand then have it where some food are fishermen/women's hooks that catch you

The basic idea behind this is you start out and hatch as a fish. You then swim around avoiding the bigger fish and hooks that are in the water. You live and eat and swim around as a fish to try and get as big as you can. No objective just live and swim.